Wipe device for windows of motor vehicles, having an elongated wiper arm, which is guided at one end on the motor vehicle and is driven

ABSTRACT

The invention relates to a wiper device for windows of motor vehicles, having an elongated, driven wiper arm ( 10 ) guided at one end on the motor vehicle, on whose other free end section an elongated wiper blade, which operates on the window, is hinged so it can oscillate in a longitudinal axially parallel manner and around a pivot axis ( 44 ) oriented transversely to the longitudinal axes. A section ( 38 ) of the wiper blade ( 14 ) is guided between two legs ( 34, 36 ), which are arranged at a distance from each other, of a connecting device ( 12 ), and hinge means of the wiper blade cooperate with hinge means of the wiper blade connecting device ( 12 ) arranged on one end of a wiper blade connecting rod, while the connecting rod is provided at its other end with a first hinge element ( 18 ), which is a part of a tilt hinge ( 20 ), and the drive means ( 24 ) of the wiper device act on the other second hinge element. A particularly advantageous wiper device results, if the wiper arm connecting rod ( 16,  or respectively  116,  or respectively  216 ) and the connecting device ( 12 ) for the wiper blade have been produced in one piece from a sheet metal plate.

BACKGROUND OF THE INVENTION

The invention relates to a wiper device. In a known wiper device of thistype (DE- AS 19 05 352), the connecting device for the wiper blade ismade of a sheet metal piece and provided with a plug-in bushing, intowhich the solid, prefabricated connecting rod must be inserted andfastened in a further process step. Besides the thickening expenseneeded for this, it is furthermore disadvantageous that this plug-inconnection between the connecting device and the connecting rodunnecessarily increases the mass which needs to be accelerated andbraked during the wiping process, something which needs to be taken intoconsideration by an appropriate layout of the drive components for thewiper device.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a wiperdevice which avoids the disadvantages of the prior art.

In keeping with these objects and with others which will become apparenthereinafter, in the present invention the wiper arm connecting rod andthe connecting device for the wiper blade are produced in one piece froma sheet metal plate which is folded in two layers in a region of theconnecting rod.

With the wiper device in accordance with the invention, the connectingdevice for the wiper arm and the connecting rod can be produced in asingle process step. The arrangement of a plug-in bushing is omitted. Aweight reduction is the result of this—also in view of the omission of asolid connecting rod—which has space-saving and cost-effective resultsin the layout of the drive components.

With another known wiper device (DE 34 20 274 A1), the first hingeelement of the tilt hinge is U-shaped in cross section and made of asheet metal piece and is riveted in the area of an overlapping sectionbetween the hinge element and the solid prefabricated connecting rod tothe latter. The production outlay required for this is considerable.Moreover, the overlapping section increases the mass which must beaccelerated and braked in the course of the wiping action, which makesthe layout of the drive components more expensive.

In accordance with another embodiment of the present invention, thewiper arm connecting rod and the first hinge element of the tilt hingeare produced in one piece from a sheet metal plate which is folded intwo layers in a region of the connecting rod.

With the wiper device in accordance with this embodiment of theinvention, the connecting rod of the wiper and the first hinge elementof the tilt hinge can be produced in a cost-effective manner in a singleproduction step. Special fastening means and an overlapping section canbe omitted. The weight savings resulting from this and from the omissionof a solid connecting rod allow a cost-effective layout of the drivecomponents of the wiper device.

A particularly advanced further embodiment of the invention results ifthe wiper arm connecting rod, the connecting device for the wiper bladeand the first hinge element of the tilt hinge are made from sheet metalin one piece, because in this case the advantages of the above mentionedindividual steps are complemented in a logical manner.

To increase the stability of the wiper arm in the area of the wiper armconnecting rod, the latter is stiffened by deformations of the sheetmetal. By means of these deformations it is possible to multiply thewiper stage and the bending moments over the entire wiper arm range.

Further advantageous developments and embodiments of the invention arerecited in the following description and in the exemplary embodimentsrepresented in the associated drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Shown in the drawings are in:

FIG. 1, a wiper arm, which is a component of a wiper device, along withits drive means, and a wiper blade, indicated by dash-dotted lines, in aperspective view,

FIG. 2, a section through a wiper arm in FIG. 1 along the line II—II inan enlarged representation,

FIG. 3, the section surface, represented in enlargement, of a sectionalong the line III—III in FIG. 1,

FIG. 4, another cross-sectional embodiment, differing from FIG. 2, ofthe wiper arm in the area of the wiper arm connecting rod,

FIG. 5, a further possible cross-sectional embodiment, differing fromFIG. 2, of the wiper arm in the area of the wiper arm connecting rod,

FIG. 6, a top view of a portion of a sheet metal plate from which theconnecting device and the connecting rod are made, and

FIG. 7, a top view of a portion of a sheet metal plate from which theconnecting device and the first hinge element of the tilt hinge aremade.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Parts of a wiper arm 10 represented in FIG. 1 are a connecting device12, with the aid of which an elongated wiper blade 14, indicated bydash-dotted lines, can be hingedly connected with the wiper arm. Theconnecting device 12 is arranged at one end of a wiper arm connectingrod 16. The other end of the wiper arm connecting rod 16 is connectedwith a first hinge element 18, which is a part of a tilt hinge 20 of thewiper arm. Moreover, a second hinge element 22, on which drive means 24for the wiper arm 10 act, is also a part of the wiper arm 10. The drivemeans are constituted by a wiper shaft, which is oscillatingly driven inthe direction of the two-headed arrow 26. Together with the wiper armconnecting rod 16 and the first hinge element 18, the connecting device12 constitutes a hinge lever 28 which, together with the wiper blade 14,can be tilted around the hinge axis 29, which essentially extendsparallel with the window surface, in the direction of the two-headedarrow 30, so that the wiper blade 14 can be lifted off the window aswell as placed back on it. Thus, the hinge movement essentially takesplace in a plane extending vertically from the window surface. The wipershaft 24 is seated on the motor vehicle, so that the second hingeelement 22 of the tilt hinge 20 constitutes the end of the wiper arm 10on the driven side, on whose free end the connecting device 12 isarranged. As shown in FIGS. 1 and 2, the connecting device 12 has anessentially U-shaped cross section. The U-base 32 of the connectingdevice 12 essentially extends in a plane parallel with the window. Thetwo U-legs 34 and 36 extend from the U-base toward the window. Betweenthe two U-legs 34 and 36 of the connecting device 12, which are locatedat a distance from each other, lies a section of the back portion 38 ofthe elongated wiper blade 14, on which hinge means, not shown in detail,for example hinge pins, are arranged, which project into seatingrecesses 40 and 42, also constituting hinge means, of the connectingdevice 12. Here, the hinge means on the back portion 38 of the wiperblade 14 and the seating recesses 40, 42 in the two U-legs 34, 36 of theconnecting device 12 are arranged in such a way that a hinge axis 44results, which essentially lies parallel with the window surface andtransversely to the longitudinal axes of the longitudinally parallelelements 14 and 28 of the wiper device. The wiper blade 14 can perform apivoting motion (two-headed arrow 46) around this hinge axis, by meansof which the wiper blade can be adapted during the wiping operation tothe changing surface contours, in particular in connection withspherically curved windows of motor vehicles. The two U-legs 34 and 36see to a correct guidance of the wiper blade 14 during the wipingoperation.

As can be seen from FIGS. 1 and 3, the first hinge element 18 of thetilt hinge 20 also has a U-shaped cross section. It therefore also has aU-base 48 and two U-legs 50 and 52, placed at a distance from each otherand extending from the U-base toward the window. The seating of the tilthinge on the hinge lever side is arranged in these two U-legs 50 and 52,while the hinge element 22 dips with a shoulder 54 between these twoU-legs and is provided with the seating on the drive side.

As FIG. 1 shows, the hinge lever 28 is made of a single piece. TheU-base 32 of the connecting device 12 makes a transition into the wiperarm connecting rod 16, which in turn makes a transition into the U-base48 of the first hinge element 18. The U-legs 34 and 36 of the connectingdevice 12 also extend in one piece via the wiper arm connecting rod 16and make a transition into the U-legs 50, 52 of the first hinge element18. In accordance with a first embodiment, the U-legs 34, 36 of theconnecting element 12 and the U-legs 50, 52 are folded together withtheir free ends 56 and 58 in the area of the wiper arm connecting rod16, as can be seen in FIG. 2. This stiffening fold is gradually formedin the transition areas 60 between the connecting device 12 and thewiper arm connecting rod 16, or respectively in the transition area 62between the wiper arm connecting rod 16 and the first hinge element 18.Independently of the embodiment of the stiffening deformation of thewiper arm connecting rod 16 represented in FIG. 2, such can also beproduced in accordance with FIG. 4 (11 b), or respectively 5 (21 b).Further embodiments of the fold are conceivable. The purpose of allpossible deformations is the achievement of the required stiffness ofthe hinge lever 28. The thickness of the sheet metal, from which theentire hinge lever 12, 16, 18 is made in one piece, can of course alsocontribute to this.

Independently of the embodiment of the hinge lever 28, or respectively12, 16, 18, drawn in FIG. 1, it is also conceivable that only theconnecting device 12 is formed in one piece on the wiper arm connectingrod 18, and that the arrangement of the first hinge element 18 isembodied in the conventional manner as disclosed in the prior art. Onthe other hand, it is also conceivable to only produce the wiper armconnecting rod 18 in one piece with the first hinge element 18 and toconnect the connecting device 12 in the manner known from the prior artwith the wiper arm connecting rod 16.

The basic form of a metallic sheet metal plate 100 is represented inFIG. 6, wherein the dashed lines 102, 104, 106 represent the bendingedges at which the plate 100 is bent, or respectively folded. By meansof appropriate folding, either a cross section of the wiper armconnecting rod 16 in accordance with FIG. 2, or a cross section of thewiper arm rod 216 in accordance with FIG. 5 can result from therepresentation in FIG. 6. Recesses 140, 142 can already be arranged inthe sheet metal plate 100 which, following the bending process, resultin the seating recesses 40, 42 of the connecting device 12.

A metallic sheet metal plate 200 represented in FIG. 7 has the initialshape for the one-piece production of the wiper arm connecting rod 16and the first hinge element 18. For this purpose, the sheet metal plate200 must be folded, or respectively bent, in accordance with the bendingedges 202 and 204 represented by dashed lines. A U-shape in accordancewith FIG. 3 then results in the area of the first hinge element, whilethe fold in the area of the wiper arm connecting rod 16 can be selectedin accordance with the embodiment in FIG. 2 or the embodiment in FIG. 5.As can further be seen from FIG. 7, it is also possible at the same timeto arrange seating recesses 206 in the sheet metal plate 200, which,following the final assembly, together with appropriate seating meansand the second hinge element 22 (FIG. 1), result in the tilt hinge 20.

If the two sheet metal plates 100 and 200 are directly combined witheach other in accordance with FIGS. 5 and 6, a single sheet metal plateresults which, with appropriate folding and deformation, results in ahinge lever 28 in accordance with FIG. 1.

In all cases the result is a wiper arm, which is constructed flat andcost-effectively and has a pleasing design and low weight and which,with appropriate selection of the material thickness and/or withappropriate design of the cross section in the area of the wiper armconnecting rod 16, has the required stiffness.

What is claimed is:
 1. A wiper device for windows of motor vehicles,having an elongated, driven wiper arm (10) guided at one end on themotor vehicle, on whose other free end section an elongated wiper blade(14), which can be placed on the window, is hinged so it can oscillatein a longitudinal axially parallel manner and around a pivot axis (44)oriented transversely to the longitudinal axes, wherein a section of thewiper blade (14) is guided between two legs (34, 36), which are arrangedat a distance from each other, of a connecting device (12), which isU-shaped in cross section, the hinge means of the wiper blade (14)cooperate with hinge means of the wiper blade connecting device (12)arranged on one end of a wiper blade connecting rod (16), and theconnecting rod (16) is provided at its other end with a first hingeelement (18) which is a part of a tilt hinge (20), on whose other secondhinge element (22) the drive means (24) of the wiper device act, whereinthe wiper arm connecting rod (16) and the connecting device (12) for thewiper blade (14) have been produced in one piece from a sheet metalplate, and in a region of the wiper arm connecting rod (16) said metalplate is folded in two layers which define parallel planar surfaces incontact with one another.
 2. The wiper device in accordance with claim1, wherein the wiper arm connecting rod (16, 116, 216), the connectingdevice (12) for the wiper blade (14) and the first hinge element (18) ofthe tilt hinge (20) have been produced in one piece from a sheet metalplate.
 3. The wiper device in accordance of claim 1, wherein the wiperarm connecting rod (16, 116, 216) has been stiffened by deformations ofthe sheet metal.
 4. The wiper device in accordance with claim 1, whereinthe metal plate in a region of the wiper arm connecting rod (16) isfolded so that free ends of the metal plate are located one against theother.